1. Energy Six Varieties

2. Energy Difficult to define – has no “substance” “The ability to perform work” Counterpart to matter EE = mc 2 Einstein work in physics led to this discovery MMatter and energy are two forms of the same thing Measured in joules (J) EEquivalent to lifting a small apple one meter

3. Potential energy SStored energy, i.e., energy that may be released in the future Sources = gravity, elasticity, chemicals Kinetic energy EEnergy of motion, or, released potential energy PProduct of mass and velocity

4. Six Varieties Mechanical Energy “Basic” energy of motion  Either kinetic or potential Work done can be considered “mechanical energy”

5. Chemical Energy Stored in chemical bonds  In attractive forces between atoms and molecules Powers flashlights, automobiles Organisms utilize chemical energy to live (food) Combustion

6. Endothermic  Heat absorbing event Ice packs, evaporation Exothermic  Heat releasing event Sodium Hydroxide and water, condensation

7. Heat Energy Amount of kinetic energy in a substance’s atoms/molecules Different from temperature  Temperature = average measure of kinetic energy  Heat = total energy  Large warm pool vs boiling pot of water  Pool = high heat, low temperature  Pot of water = low heat, high temperature

8. Electrical Energy Electric charge  Property of subatomic particles (protons, electrons)  Used in electronics to “do work”

9. Electromagnetic Energy (Radiation) Light energy VVisible, infrared, ultraviolet, x-rays, gamma rays CComes in photon packets Behaves like matter and/or energy, depending on the situation WWave/particle duality

10. Nuclear Energy Energy from subatomic bonds  Nuclear force – fundamental force When nuclear bonds are broken  Nuclear explosion  E = mc 2 tremendous energy from little mass

11. Conservation of Energy Energy cannot be created or destroyed  Law of conservation of matter and energy Energy can be transformed from one type to another

12. Energy Transformation Any type can be transformed into any other type  Light and heat are related  Mechanical to electric, vice versa  Chemical to heat